725217509 has 2 divisors, whose sum is σ = 725217510. Its totient is φ = 725217508.

The previous prime is 725217487. The next prime is 725217539. The reversal of 725217509 is 905712527.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 723448609 + 1768900 = 26897^2 + 1330^2 .

It is a cyclic number.

It is not a de Polignac number, because 725217509 - 2⁸ = 725217253 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (725217539) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 362608754 + 362608755.

It is an arithmetic number, because the mean of its divisors is an integer number (362608755).

Almost surely, 2^725217509 is an apocalyptic number.

It is an amenable number.

725217509 is a deficient number, since it is larger than the sum of its proper divisors (1).

725217509 is an equidigital number, since it uses as much as digits as its factorization.

725217509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 44100, while the sum is 38.

The square root of 725217509 is about 26929.8627735085. The cubic root of 725217509 is about 898.4407193950.

The spelling of 725217509 in words is "seven hundred twenty-five million, two hundred seventeen thousand, five hundred nine".